If you've checked your electrical panel and the oven circuit is in the open position, the next common problem is that the oven timer needs to be set.
This is especially noticeable if the oven timer is blinking.
Some ovens require a timer to be set before any other functions can work.
Setting an oven timer usually involves holding down multiple buttons until the time flashes, then using the + and - buttons to set it to the correct time. For specific information on your oven make and model, see the instruction manual that came with your oven.
However, a timer may be set and your oven still isn't working.
If setting a timer doesn't fix your oven, the problem is usually slightly more complicated and may involve a burnout or faulty wiring or a faulty switch.